Tech built to find missing aircraft not always used

Jaikumar Vijayan |
March 12, 2014

Aviation experts have cited multiple possible reasons for the problems in the multi-country effort to locate the Malaysia Airlines jetliner that dropped off the grid over the South China Sea four days ago.

The major aircraft tracking technologies include Automatic Dependent Surveillance-Broadcast (ADS-B), said Ric Peri, vice president of government and industry affairs at the Aircraft Electronics Association. Rather than relying on a radar ping, ADS-B uses a GPS signal and an aircraft's navigation system to determine the position of a flight and then broadcast that information, he said.

Many U.S carriers have begun using the technology — all major commercial aircraft in the U.S are required to use it by 2020, he said. The technology has proved especially useful over areas like the span of Atlantic Ocean between Hudson Bay in Canada and the Irish coast that lack radar coverage, he said.

Other regions of the world, though, still depend entirely on radar signals, he noted.

The missing Malaysian airliner was also a Boeing 777, which was first used nearly 20 years ago. "The electronics and the technology that was in the aircraft was probably certified in the five-year time frame before that," Peri said. Certification of such technology takes time, so it's not unreasonable to conclude that the missing aircraft may have carried 30-year old tech, he added.

The aircraft Flight Data Recorder and Cockpit Voice Recorder should each have had attached beaconing devices designed to activate if the aircraft crashed into the sea. The beaconing system is designed to last for about 30 days underwater. "But those are basically homing beacons, so they are fairly low power," Peri said.

It's also unclear with the lost aircraft carried an Emergency Location Transmitter (ELT) that's designed to transmit an emergency signal in the case of an accident.

"If in fact the aircraft had a crash, a force switch built into the unit would turn it on," Peri said. The device would broadcast a signal that would be picked up by Search and Rescue Satellite Aided Tracking (SARSAT), a worldwide search and rescue monitoring system used to locate everything from missing hikers to missing airlines, he said.

U.S. commercial aircraft are required to have an ELT.

It's quite unusual for an ELT not to work as designed, Graham said.

"It takes a long time and a lot of testing and certification trials to change the way things are done in commercial aviation," Graham said. "Look how long the iPad was out before the FAA [cleared] it for use in the cockpit. And actually, that was pretty fast, comparatively speaking."

Experts noted that some airlines, especially those outside of North America and Western Europe, often lack the latest tracking and emergency technologies.